package com.dipacommerce.dipasport.utils.imagezoom;

import android.content.Context;
import android.util.FloatMath;
import android.util.Log;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.ViewConfiguration;

public class CupcakeGestureDetector implements GestureDetector {

    protected OnGestureListener mListener;
    private static final String LOG_TAG = "CupcakeGestureDetector";
    float mLastTouchX;
    float mLastTouchY;
    final float mTouchSlop;
    final float mMinimumVelocity;

    @Override
    public void setOnGestureListener(OnGestureListener listener) {
        this.mListener = listener;
    }

    public CupcakeGestureDetector(Context context) {
        final ViewConfiguration configuration = ViewConfiguration.get(context);
        mMinimumVelocity = configuration.getScaledMinimumFlingVelocity();
        mTouchSlop = configuration.getScaledTouchSlop();
    }

    private VelocityTracker mVelocityTracker;
    private boolean mIsDragging;

    float getActiveX(MotionEvent ev) {
        return ev.getX();
    }

    float getActiveY(MotionEvent ev) {
        return ev.getY();
    }

    public boolean isScaling() {
        return false;
    }

    @Override
    public boolean onTouchEvent(MotionEvent ev) {
        switch (ev.getAction()) {
        case MotionEvent.ACTION_DOWN: {
            mVelocityTracker = VelocityTracker.obtain();
            if (null != mVelocityTracker) {
                mVelocityTracker.addMovement(ev);
            } else {
                Log.i(LOG_TAG, "Velocity tracker is null");
            }

            mLastTouchX = getActiveX(ev);
            mLastTouchY = getActiveY(ev);
            mIsDragging = false;
            break;
        }

        case MotionEvent.ACTION_MOVE: {
            final float x = getActiveX(ev);
            final float y = getActiveY(ev);
            final float dx = x - mLastTouchX, dy = y - mLastTouchY;

            if (!mIsDragging) {
                // Use Pythagoras to see if drag length is larger than
                // touch slop
                mIsDragging = FloatMath.sqrt((dx * dx) + (dy * dy)) >= mTouchSlop;
            }

            if (mIsDragging) {
                mListener.onDrag(dx, dy);
                mLastTouchX = x;
                mLastTouchY = y;

                if (null != mVelocityTracker) {
                    mVelocityTracker.addMovement(ev);
                }
            }
            break;
        }

        case MotionEvent.ACTION_CANCEL: {
            // Recycle Velocity Tracker
            if (null != mVelocityTracker) {
                mVelocityTracker.recycle();
                mVelocityTracker = null;
            }
            break;
        }

        case MotionEvent.ACTION_UP: {
            if (mIsDragging) {
                if (null != mVelocityTracker) {
                    mLastTouchX = getActiveX(ev);
                    mLastTouchY = getActiveY(ev);

                    // Compute velocity within the last 1000ms
                    mVelocityTracker.addMovement(ev);
                    mVelocityTracker.computeCurrentVelocity(1000);

                    final float vX = mVelocityTracker.getXVelocity(), vY = mVelocityTracker.getYVelocity();

                    // If the velocity is greater than minVelocity, call
                    // listener
                    if (Math.max(Math.abs(vX), Math.abs(vY)) >= mMinimumVelocity) {
                        mListener.onFling(mLastTouchX, mLastTouchY, -vX, -vY);
                    }
                }
            }

            // Recycle Velocity Tracker
            if (null != mVelocityTracker) {
                mVelocityTracker.recycle();
                mVelocityTracker = null;
            }
            break;
        }
        }

        return true;
    }
}
